Manufacture of leather



'WZLLIAM O. BLATZ, 0F WILMINGTON, DELAWARE, ASSIGI OR OF ONE-HALF IO JGHN B. BLATZ, OF PHILADELPHIA, PENll'ElYLVANl'A.

MANUFACTURE OF LEATHER.

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Ito Brewing. Application filed February 5. 1917. Serial No. 146,734.

Specification of Letters Patent.

citizen of the United States, and a resident o'l l l ilmington, New Castle county, Delaware. have invented certain ln'iproveinents the lvlanulacture of Leather, or which the following is a specification.

My invention relates to the manufacture of leathen, and the object of my present invention is to produce a White leather available for general use in the arts and particularly valuable for the manufacture of shoes and other forms of footwear.

My invention comprises the precipitation of an insoluble barium salt within and upon the surlace, body and fibers of a skin or ride during or subsequent to the tanning or lowing operation. for the purpose of producin a white leather; the barium salt not only precipitating in a White state, thus deternliningand liningthe linal color ol the leather produced from the hide or skin operated up 1. but also neutralizing ans;- coloration that may have been imparted by the tanning or sawing operation, whether the latter includes a chrome treatment or not. so that the leather, when finished is a pure white product.

The purpose oi my invention is the precipitation ol an insoluble barium salt, with in and upon the surface, body and fibers ot' skins" and hides tawed or tanned by any process involving a chrome treatment 0' a modified chrome treatment, and while 1 propose to carr thi into eil'ect in conncetimi h hides and skins tawed or tanned. by a i nubination process which may include an alum treatment followed by a chronic treat do not wish to be limited to any irl'icular method or prorss of tanning or tuning a skin or hide involvingthe use of chrome preliminary to carrying out my lin moved process oi precipitating an insoluble hurium salt within and upon the surface, body and El rs of the skins or hides for the purpose of producin a White leather prodnot.

The improved white product made in accordance with my invention differing from i i not all,v White leathers including rec leathers, is susceptible of receivi or polish under a glazing operation, and this glazing operation has the effeet of not onl improving the character of the leather. but also of closing; the pores ot the skin or hide and increasing the moisture resistant properties of the final leather product.

M invention is based upon the discovery that an insoluble barium salt may be pre cipitatcd within and upon the surface, body and fibers of the skin or hide by subjecting the ame at a certain stage of the tanning or taw ng treatment, or after the tanning or tawin treatment is completed, to the action of a soluble salt of barium with a salt (such 'zis sodium sulfate or its equivalent for the desired purpose) capable oi? reacting there with to produ ire an insoluble precipTatc of barium in a White state; the resulting rcactiou precipitating the barium salt Within. and upon the surface. body and fibers of the skin or hide undergoing treatment and retaining; it in the final leather product re sulting from the complete treatment of such hide or skin. in other i that ma be formed have no effect upon tne skin or hide under treatment. and usually pass to Waste.

7 he precipitation (ii an insolublev barium salt within and upon the surface, body and fibers of the skin or hidc during or following' the process of transforming the same into leather, produces a condition of whiteness that-is permanent, since the barium salt is insoluble and can not be washed from the finished leather.

ll/hile it is possible that other salts including metallic salts or the salts oi other alkaline earth metals may be precipitated within and upon the surlzu e. body and fibers ol eather For the purpose oi producing a white product. barium possesses a munbcr of characteristics which malco it peculiarly raluablc and desirable for the described pu pose. in the first place, it is one of the most inert salts l uo\\'u bump; insoluble in Water and substantially insoluble in acids, and it precipitates absolutcly White in the skin or hido to which it is subjected under my improved nufhod or process oi treatment.

in carrying out my improved process for the production o'l White leather from skins and hides. l may proceed s1ilistantiall as Follows:

The skins. after being prepared for tauhing or tawin by any method. which prep-- weenie yolk; flour; alum, and common salt, preferably in a drum, and the treatment of the skins following the application of the tawq ing paste may be substantially that of any of the .chrome'tawin'g or tanning processes now in common use.

. Prior to the usual finishing steps to which the hides or skins are subjected when the tanning or tawing treatment proceeds in the usual manner, and the tanning or tawing operation being complete or substantially so, the treatment which characterizes"my invention may be commenced, and to the usual hypo-solution which, fol; one hundred (100) pounds of skins or hides,ma v consist approximately of I i 1 Hyposulfite of soda 15.0% Muriatic (or sulfuric) acid- .5%

with suilicient water to provide a bath having a volume of approximately fifteen (15) gallons; (the amount of'hypo being somewhat greater than that usually employed,) I add about(i% of a soluble salt such as p0- tassium sulfate; sodium sulfate; magnesium sulfate; ammonium oxalate; etc, etc, or any equivalent salt capable-of-perforn1ing the desired function. This addition is made to the usual hypo-solution employed in the tanning process, or what may be termed it spent solution of the same after the usual hypo treatment of the hides or skins. The skins are then drummed in this special solution or bath for approximately three (3) to four (4) hours, and may remain in the same over night. T

The special hypo-solution is then drained ofl} and about 11% of a barium salt in solution inapproxiinately six (6) gallons of watcris placed in the drummmlthe skins aredrummed fora shortperiodof time: the barium salt reacting with any .solublc salt left in the bath, after which the excess so.

lution orliqnor is drained ofl. Following this treatment, about 7% of a suitable soluble salt (such as indicated above or any equivalent capable of performing the dcsircd function) capable of reacting with the barium salt to form an insoluble precipitate. in solution in approximately six ((3) gallons of water, is placed in the drum. and the skins are drummed in this bath for about one (1 hour, after which about 11% of the barium salt employed in solution in approximately six (6) gallons of water is added to the bath in the. drum, and the skins are again drummed for a short period of time.

This alternating treatment of the tanned or tawed skins or hides for proper periods time with the ibnriiun salt and a salt capa ble of producing an insoluble barium )recipitate, separately and together, both 0 which agents may be in'excess, insures a complete precipitation of an insoluble barium salt within and upon the surface, body and fibers ofthe skin or hide undergoing treatment, with the resulting whiteness desired, and afteigtlie final preclpitation the skins are taken out of the drum, struck out inthe usual way; dried, and staked. The skins so prepared are permanently 'white leather, ready for the market or, if desired, they may be subjected to a final glazing or ironing operation. My improved-white leather when glazed is a substantially moisture-resistant product.

If desirable for any reason, the skins may be subjected to a fat-liquor treatment to soften them should they be harsh or in. a condition that would justify application of the fat-liqudr treatment, before beingdried out preliminary to the staking operation and the subsequent ironing or glazing operations.

It will be understood, of course, that I may employ a two-bath method of chrome J0 tawing or tanning for the preliminary treatment of the skins, or a one-bath process of any of the well known types,'or the :usual basic chrome tannage, and while the steps of any usual chrome tannage process may be followed and the 'n'iaterials of such process employed in the tawing or tanning or other treatment of the skins or hides prior to the precipitation of an insoluble barium salt, in f such skins or hides, the amount of such Inaterfials used is considerably modified; for instance less bichromate of potash, (or soda) and acid (muriatic or sulfuric) may be used, with a considerably greater quantity of hyposulfite of soda than is employed with the usual chrome tannage. I I My improved leather product may be de-- scribed as a chrome-tanned white leather.

I am aware that attempts have been made to produce white leather from chrome-tanned skins but without success, and in all prior efforts to produce white leather, no practical use has been made of chrome tannage on account of the coloring in'iparted by the chrome. 11;,

I have succeeded in producing a permanent white leather from chrome-tanned skins through a new and original process which comprises: ((1'). reduction of the amount of color resulting from the regular chrome proc- 12o css, and (1)); an impregnation of the skin with an insoluble white precipitate, barium being preferred. The white leather obtained by this method will ndthstaml the glazing operation employed in the manufacturc of ordinary glazcd'kid. and is improved by such glazing. The white leather made in accordance with my invention will not only withstand washing with a cloth wet with Water but is,

ractically speaking, a white washable eathcr. l or the making of white shoes. whether employed for the complete upper or for the top alone, it-is decidedly superior to any of the so- *alled white leathers hcretd fore manufactured.

As this application possesses matter in common with an application filed by me Biovember 1(3, 1918. Serial No. 131,707, it is to be trea'ted as a continuation of said prior application as far as the common subjectmatter is oncerned.

I claim:

l. 'The process oi treating skins or hides for-the production of white leath r therefrom, which comprises tanning or *tawing the same by a chrome treatment, and then precipitalin; an insoluble 'hite salt one of the alkaline earth metals within and upon the surface. body and libers of the. skins or hides to determine and fix the whiteness of the finished product.

The process olf treating sl-zins or hides for the production ol white leather there from, which comprises suhjcclir them. to alum-tannage. then to chrome treatment, and then precipitating au. insoluhle white salt oi one of the alkaline earth metals within and upon the surface. l)()il and fibers ol' the "kins or hides to determine and fix the whitene s oi the linished product.

3. The process of lreatiuc skins or hides tor the production of white leather then-r from, which comprises tanning or tawine the same by a modified chrome treatment, and then precipitating an insoluble white salt of one of the alkaline earth metals within and upon the surface, body and fibers of the skins or hides to determine and fix the whiteness of the finished product.

-l-. The process of treating skins or hides for the production oi' white leather therefrom, which comprises sub' iecting them to a modified aluiii-treatment. then to a, modified chrome treatment, and then precipitating an insoluble white salt of one oi the,

a kaline earth metals within and upon the surface, body and fibers of the skins or hides to determine and fixithe whiteness of the finished product.

The process of prodiu-inp white leather. which comprises tawinc; or tanni g sins or hides by a chrome treatment, and the vrecipitatingz an within and upon the surface, body and fibers oi" the same.

6. The process of treating: skins or for the production of white leal refrom, which comprises subjecting: them to aliuii tannagze, then to chrome treatment. and finally to the successive action of a barium salt and a salt capable of precipitat ing' the barium sali in an insoluble state within and upon the suriace, bed and fibers of the skins or hides insoluble barium salt hides T. The process of treating skins or hides, which comprises subjecting them to a modilied chrome treatment whereby the usual chrome coloration is modified, and then to the successive action of a barium salt and a salt capable of precipitating the, barium salt in an insolulde state within and upon thesurface, body and fibers of the skins or hides to produce a white leather.

8. The process of treating skins or hides for the production or white washable glazed leather therefrom, whichcomprises subjecting them to chrome treatment, then to the. successive action. of a barium salt and a salt capable of precipitating the barium in an insoluble state within and upon the surface, Ody and fibers of the skins or hides, drying and finishing the skins or hides, and then glazing the same 9. T he process of treating; skins or hides for the production of white Washable glazed lair-her therefrom, which comprises suhl, ting them to alum tannage, then to crome treatment, then to the successive action of a hariun'r salt and a salt capable of precipitating the barium salt in an insoluble state within and upon the surface, body and lihcrs oi the skins or hides, drying and finishing the skins or hides, and then glazing 'tl same.

10. T Le process of treating skins or hides for the production of white washable glazed leather. which. comprises subjecting them to a modified chrome treatment whereby the usual chrome coloration is modified, then to the successive action of a barium salt and a salt capable of precipitating the barium in an insoluble state within and upon the surface, body and of the skins or hides, drying and finishing the skins or hides and !.l j; aim: the same.

ll. The process oi treating skins or hides for the production of white leather, which (annprises tawing or tanning" the same by a chrome treatment. and then subjecting the skins or hides to the si'iceessive action of a soluble sulfate and barium chlorid la(l l wherehy barium sulfate is precipitated within and upon the surt'ace. body and fibers or the skins or hides.

iii The process nth-eating skins or hides tor the production oi white leather, which comprises ta'wing or banning the same by a chrome. treatment and then subjecting the skins or hides to the succi-iss-ive action of sodium sulfate (Kahlil) and barium chlorid ll iai l l whereby barium sulfate is precipi tated within and upon the surface, body and lihers oi th e skins or hides.

.l The process of treating); skins or hides for the pioductimi oi leather therefrom, which comprises subjecting them to alum tannage, then to chronic treatment, and fina to the successive action of a soluble sulfate and barium chlorid (BaCn), where-.

by barium sulfate is precipitated within and I upon the surface body and fibers of the skins or hides.

14. The process of treating skins or hides for the production of leather therefrom, which comprises subjecting them -to alumtannage, then to chrome treatment, and

finally to the successive action of sodium sulfate (re son and barium chlorid (BaCh) whereby barium sulfate is precipitated within and upon the surface, body and fibers of the skins or hides.

15. The process of treating skins or hides, which comprises subjecting them to-a modified alum-treatment, then to a modified chrome treatment, and finally to the successi-ve action of a soluble sulfate and barium chlorid (BaCl,) whereby barium sulfate is precipitated within and upon. the surface;

body and fibers of the skins or hides.

16. The process of treating skins or hides, which comprises subjecting them to a modi fied alum'treatment, then to a modified chrome treatment, and finally to the successive action of sodlum sulfate (Na SO and barium ehlorid (BaCh) whereby barium sulfate is precipitated within and upon the surface, body and fibers of the skins or hides. r

17. The method or process of producing White glazed leather, which comprises tawf mg or tanning skins or hides by achrome treatment, then subjecting the skins 01 hides to the successive actlon -of sodium sulfate (Na SO,) and barium chlorid (BaCl 'whereby the surface, body and fibers of the skins ,or hides are impregnated with barium in an. insoluble state; such impregnation de- .are impregnated with barium in an insoluble state; such impregnation determining and fixing the whiteness of the finished product, drying and finishing the skins or hides, and finally glazing the same.

19. In the process of tawing or tanning skins or hides, the step which comprises the white leather made esa-are precipitation of an insoluble white salt of.

one of the alkaline earth metals within and upon the surface, body and fibers of a chrome-treated .skin or hide to produce a white leather.

20. In the process of tawing or tanning skins or hides, the step which comprises the precipitation of barium sulfate within and upon the surface, body and fibers of a dhrome-treated skin or hide to produce a white leather.

21. As a new article of manufacture, white leather made from chrome-treated skins or hides and having its surface, body and fibers impregnated with an insoluble white salt of one of the alkaline earth metals.

22-. As' a new article of manufacture, white leather made from chrome-treated skins or hides having its surface, body and fibers impregnated with a barium salt in an insoluble state to determine and fix the whiteness of the same.

As a new article of manufacture, from. chrome-treated skins or hides andhaving its surface, body and fibers impregnated with barium sulfate.

24. As. a new article of manufacture, glazed white leather made from chrometreated skins or hides and having its surface, body and fibers impregnated with a barium salt in an insoluble state.

25. As a new article of manufacture, alum-chrome-tanned leather white in color and having its surface, body and fibers impregnated with a barium salt in an insoluble state to determine and fix the whiteness of the same.

926. As a new article of manufacture. a white chrome-tanned leather, unchange able in color by washing operations, and having its surface, body and fibers impregnated with a barium salt in an insoluble state.

27. As a new article of manufacture, glazed white washable leather made from chrome-treated skins or hides and having its surface, body and fibers impregnated with a barium salt in an insoluble state.

28. As a new article of. manufacture, glazed white washable leather made from alum-chrome-treatedskins or hides and having its surface, body and fibersimpregnated with a barium salt in an insoluble state.

VVILLTA M (f BLATZ. 

